1. Field of the Invention
The present invention relates in general to treatment of depression and depressive symptoms, and more particularly, to of treatment using phototherapy of brain tissue.
2. Description of the Related Art
In the U.S., it is believed that approximately 10% of people suffer from depression at any one time, and 20%-25% suffer an episode of depression at some point during their lifetimes. The disease affects people of all ages, including children, adults, and the elderly, and disproportionally affects women, with about twice as many women as men suffering from depression at some point in their lives. Additionally, persons who suffer one episode of major depression are much more likely to have additional episodes than those who have not experienced serious depression.
There are several types of depression which vary in severity and average episode length. Two of the most common types are major depression and chronic depression or Dysthmia. Chronic depression is generally a less severe form of depression, having milder but longer lasting symptoms than major depression. The symptoms of both types of depression are essentially the same, and include sadness, loss of energy, feelings of hopelessness, difficulty concentrating, insomnia, and irritability. Individuals suffering depression are also more likely to engage in drug or alcohol abuse, and if untreated, depression can lead to violence, including suicide.
All types of depression, including major and chronic depression, are commonly treated by one or both of antidepressant medication and psychotherapy. Other forms of treatment, such as electroconvulsive therapy (ECT) are also used, albeit less frequently. There are several types of antidepressant medications presently available, including tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs), selective serotonin reuptake inhibitors (SSRIs), and selective norepinephrine reuptake inhibitors (SSNRIs). Although the widely prescribed SSRIs cause fewer severe side effects than the older TCA and MAOI drugs, they are not without their own unpleasant effects, including dizziness, insomnia, and reduced sexual desire and performance. Despite their widespread use, antidepressant medications are only moderately successful, helping only about 70% of the people who take them.
Against this background, a high level of interest remains in finding new and improved methods for the treatment of depression that exhibit higher rates of effectiveness and fewer side effects of available drug therapy.